Nest: Fix several issues with pflags

There were some confusion about validity and usage of pflags, which
caused incorrect usage after some flags from (now removed) protocol-
specific area were moved to pflags.

We state that pflags:

 - Are secondary data used by protocol-specific hooks
 - Can be changed on an existing route (in contrast to copy-on-write
   for primary data)
 - Are irrelevant for propagation (not propagated when changed)
 - Are specific to a routing table (not propagated by pipe)

The patch did these fixes:

 - Do not compare pflags in rte_same(), as they may keep cached values
   like BGP_REF_STALE, causing spurious propagation.

 - Initialize pflags to zero in rte_get_temp(), avoid initialization in
   protocol code, fixing at least two forgotten initializations (krt
   and one case in babel).

 - Improve documentation about pflags

1 files changed, 0 insertions, 1 deletions

diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c
index 7ce2fd63..ddbc9226 100644
--- a/proto/bgp/packets.c
+++ b/proto/bgp/packets.c
@@ -1464,7 +1464,6 @@ bgp_rte_update(struct bgp_parse_state *s, const net_addr *n, u32 path_id, rta *a
   rta *a = rta_clone(s->cached_rta);
   rte *e = rte_get_temp(a, s->last_src);
 
-  e->pflags = 0;
   rte_update3(&s->channel->c, n, e, s->last_src);
 }